diff --git a/src/calibre/srv/metadata.py b/src/calibre/srv/metadata.py
index d1b1adf0b9..8f9370d8a0 100644
--- a/src/calibre/srv/metadata.py
+++ b/src/calibre/srv/metadata.py
@@ -157,7 +157,7 @@ def categories_settings(query, db):
     if partition_method not in {'first letter', 'disable', 'partition'}:
         partition_method = 'first letter'
     try:
-        collapse_at = max(0, int(query.get('collapse_at', 25)))
+        collapse_at = max(0, int(float(query.get('collapse_at', 25))))
     except Exception:
         collapse_at = 25
     sort_by = query.get('sort_tags_by', 'name')
diff --git a/src/pyj/book_list/prefs.pyj b/src/pyj/book_list/prefs.pyj
new file mode 100644
index 0000000000..d2f650f80c
--- /dev/null
+++ b/src/pyj/book_list/prefs.pyj
@@ -0,0 +1,213 @@
+# vim:fileencoding=utf-8
+# License: GPL v3 Copyright: 2016, Kovid Goyal <kovid at kovidgoyal.net>
+
+from dom import clear
+from elementmaker import E
+from book_list.globals import get_session_data
+
+# from book_list.theme import get_font_size, get_color
+
+pp_counter = 0
+widget_counter = 0
+
+class ConfigItem:
+
+    def __init__(self, item_data):
+        nonlocal widget_counter
+        widget_counter += 1
+        self.widget_id = 'pref-widget-' + widget_counter
+        self.item_data = item_data
+        self.ignore_ui_value_changed = False
+
+    def initialize(self):
+        self.ignore_ui_value_changed = True
+        try:
+            self.to_ui(self.from_storage())
+        finally:
+            self.ignore_ui_value_changed = False
+        return self
+
+    @property
+    def container(self):
+        return document.getElementById(self.widget_id)
+
+    @property
+    def control(self):
+        return self.container.lastChild
+
+    def from_storage(self):
+        val = get_session_data().get(self.item_data.name)
+        if self.item_data.from_storage:
+            val = self.item_data.from_storage(val)
+        return val
+
+    def to_storage(self, val):
+        if self.item_data.to_storage:
+            val = self.item_data.to_storage(val)
+        get_session_data().set(self.item_data.name, val)
+
+    def defval(self):
+        return get_session_data().defval(self.item_data.name)
+
+    def ui_value_changed(self):
+        if self.ignore_ui_value_changed:
+            return
+        self.to_storage(self.from_ui())
+
+    def to_ui(self, val):
+        pass
+
+    def from_ui(self):
+        pass
+
+class Choices(ConfigItem):
+
+    def __init__(self, item_data, container, onfocus):
+        ConfigItem.__init__(self, item_data)
+        div = E.div(
+            id=self.widget_id,
+            E.span(item_data.text + ': ', style='white-space:pre'),
+            E.select(required='1')
+        )
+        container.appendChild(div)
+        select = div.lastChild
+        for choice, text in item_data.choices:
+            select.appendChild(E.option(text, value=choice))
+        select.addEventListener('change', self.ui_value_changed.bind(self))
+        select.addEventListener('focus', onfocus)
+
+    def to_ui(self, val):
+        self.control.value = val
+
+    def from_ui(self):
+        return self.control.value
+
+class CheckBox(ConfigItem):
+
+    def __init__(self, item_data, container, onfocus):
+        ConfigItem.__init__(self, item_data)
+        div = E.div(
+            id=self.widget_id,
+            E.input(type='checkbox'),
+            E.span(' ' + item_data.text, style='white-space:pre')
+        )
+        container.appendChild(div)
+        control = div.firstChild
+        control.addEventListener('change', self.ui_value_changed.bind(self))
+        control.addEventListener('focus', onfocus)
+
+    @property
+    def control(self):
+        return self.container.firstChild
+
+    def to_ui(self, val):
+        self.control.checked = bool(val)
+
+    def from_ui(self):
+        return bool(self.control.checked)
+
+class SpinBox(ConfigItem):
+
+    def __init__(self, item_data, container, onfocus):
+        ConfigItem.__init__(self, item_data)
+        div = E.div(
+            id=self.widget_id,
+            E.span(item_data.text + ': ', style='white-space:pre'),
+            E.input(type='number', step='any', min='1', max='100')
+        )
+        container.appendChild(div)
+        control = div.lastChild
+        for attr in str.split('min max step'):
+            val = item_data[attr]
+            if val is not undefined and val is not None:
+                control.setAttribute(attr, '' + val)
+        control.addEventListener('change', self.ui_value_changed.bind(self))
+        control.addEventListener('focus', onfocus)
+
+    def to_ui(self, val):
+        self.control.value = val
+
+    def from_ui(self):
+        return self.control.value
+
+class LineEdit(ConfigItem):
+
+    def __init__(self, item_data, container, onfocus):
+        ConfigItem.__init__(self, item_data)
+        div = E.div(
+            id=self.widget_id,
+            E.span(item_data.text + ': ', style='white-space:pre'),
+            E.input(type='text')
+        )
+        container.appendChild(div)
+        control = div.lastChild
+        control.addEventListener('change', self.ui_value_changed.bind(self))
+        control.addEventListener('focus', onfocus)
+
+    def to_ui(self, val):
+        self.control.value = val or ''
+
+    def from_ui(self):
+        return self.control.value or ''
+
+class PrefsPanel:
+
+    def __init__(self, interface_data, book_list_container):
+        nonlocal iv_counter
+        pp_counter += 1
+        self.container_id = 'prefs-panel-' + pp_counter
+        style = ''
+        div = E.div(
+            id=self.container_id, style='display:none',
+            E.style(style, type='text/css')
+        )
+        book_list_container.appendChild(div)
+        self.widgets = []
+
+    @property
+    def container(self):
+        return document.getElementById(self.container_id)
+
+    @property
+    def is_visible(self):
+        self.container.style.display == 'block'
+
+    @is_visible.setter
+    def is_visible(self, val):
+        self.container.style.display = 'block' if val else 'none'
+
+    def init(self, data):
+        c = self.container
+        clear(c)
+        self.widgets = []
+
+        def onfocus(name):
+            return def(ev):
+                c = self.container
+                div = c.querySelector(str.format('div[data-name="{}"]', name))
+                div.lastChild.style.display = 'block'
+
+        for item in data:
+            div = E.div(
+                style='margin-bottom:1ex; padding: 1ex 1em; border-bottom: solid 1px currentColor',
+                title=item.tooltip,
+                data_name=item.name,
+                E.div(),
+                E.div(
+                    item.tooltip or '',
+                    style='font-size:0.8rem; font-style: italic; margin-top:1ex; display:none'
+                )
+            )
+            c.appendChild(div)
+            val = get_session_data().get(item.name)
+            if item.from_storage:
+                val = item.from_storage(val)
+            if item.choices:
+                cls = Choices
+            elif val is True or val is False:
+                cls = CheckBox
+            elif type(val) == 'number':
+                cls = SpinBox
+            else:
+                cls = LineEdit
+            self.widgets.append((new cls(item, div.firstChild, onfocus(item.name))).initialize())
diff --git a/src/pyj/book_list/search.pyj b/src/pyj/book_list/search.pyj
index e60da5ead0..d55d344303 100644
--- a/src/pyj/book_list/search.pyj
+++ b/src/pyj/book_list/search.pyj
@@ -85,20 +85,22 @@ class SearchPanel:
         self.tag_path = []
         self.active_nodes = {}
         if not self.initial_load_started:
+            self.initial_load_started = True
             self.refresh()
         else:
             self.render_tag_browser()
 
     def refresh(self):
         if self.currently_loading is not None:
-            return
-        self.initial_load_started = True
+            self.currently_loading.abort()
+            self.currently_loading = None
         sd = get_session_data()
         query = {'library_id': self.interface_data.library_id}
         for k in str.split('sort_tags_by partition_method collapse_at dont_collapse hide_empty_categories'):
             query[k] = sd.get(k) + ''
-        self.currently_loading = ajax('interface-data/tag-browser', self.on_data_fetched.bind(self), query=query, bypass_cache=False)
-        self.currently_loading.send()
+        xhr = ajax('interface-data/tag-browser', self.on_data_fetched.bind(self), query=query, bypass_cache=False)
+        xhr.send()
+        self.currently_loading = xhr
 
     def on_data_fetched(self, end_type, xhr, ev):
         self.currently_loading = None
@@ -383,6 +385,68 @@ class SearchPanel:
                 parts.push(expr)
         self.search_control.value = parts.join(' ')
 
+    def get_prefs(self):
+        return [
+            {
+                'name': 'sort_tags_by',
+                'text': _('Sort tags by'),
+                'choices': [('name', _('Name')), ('popularity', _('Popularity (number of books)')), ('rating', _('Average rating'))],
+                'tooltip': _('Change how the tags/authors/etc. are sorted in the Tag Browser'),
+            },
+
+            {
+                'name':'partition_method',
+                'text':_('Tags browser category partitioning method'),
+                'choices':[('first letter', _('First Letter')), ('disable', _('Disable')), ('partition', _('Partition'))],
+                'tooltip':_('Choose how tag browser subcategories are displayed when'
+                            ' there are more items than the limit. Select by first'
+                            ' letter to see an A, B, C list. Choose partitioned to'
+                            ' have a list of fixed-sized groups. Set to disabled'
+                            ' if you never want subcategories.'),
+            },
+
+            {
+                'name':'collapse_at',
+                'text':_('Collapse when more items than'),
+                'min': 5, 'max':10000, 'step':5,
+                'from_storage':int, 'to_storage':int,
+                'tooltip': _('If a Tag Browser category has more than this number of items, it is divided'
+                             ' up into subcategories. If the partition method is set to disable, this value is ignored.'),
+            },
+
+            {
+                'name': 'dont_collapse',
+                'text': _('Categories not to partition'),
+                'tooltip': _('A comma-separated list of categories in which items containing'
+                             ' periods are displayed in the tag browser trees. For example, if'
+                             " this box contains 'tags' then tags of the form 'Mystery.English'"
+                             " and 'Mystery.Thriller' will be displayed with English and Thriller"
+                             " both under 'Mystery'. If 'tags' is not in this box,"
+                             ' then the tags will be displayed each on their own line.'),
+            },
+
+            {
+                'name': 'hide_empty_categories',
+                'text': _('Hide empty categories (columns)'),
+                'from_storage': def(x): return x.toLowerCase() == 'yes';,
+                'to_storage': def(x): return 'yes' if x else 'no';,
+                'tooltip':_('When checked, calibre will automatically hide any category'
+                            ' (a column, custom or standard) that has no items to show. For example, some'
+                            ' categories might not have values when using virtual libraries. Checking this'
+                            ' box will cause these empty categories to be hidden.'),
+            },
+
+        ]
+
+    def apply_prefs(self):
+        container = self.tb_container
+        clear(container)
+        container.appendChild(E.div(
+            style='margin: 1ex 1em',
+            _('Reloading tag browser with updated settings, please wait...'))
+        )
+        self.refresh()
+
     @property
     def container(self):
         return document.getElementById(self.container_id)
diff --git a/src/pyj/book_list/ui.pyj b/src/pyj/book_list/ui.pyj
index 3c0e7f4d67..659224e3f4 100644
--- a/src/pyj/book_list/ui.pyj
+++ b/src/pyj/book_list/ui.pyj
@@ -6,6 +6,7 @@ from book_list.search import SearchPanel
 from book_list.top_bar import TopBar
 from book_list.views import BooksView
 from book_list.item_list import ItemsView, create_item
+from book_list.prefs import PrefsPanel
 from gettext import gettext as _
 from utils import debounce
 
@@ -20,9 +21,13 @@ class BarState:
 
 class ClosePanelBar(BarState):
 
-    def __init__(self, title, tooltip=''):
+    def __init__(self, title, tooltip='', close_callback=None):
         tooltip = tooltip or _('Close this panel')
-        BarState.__init__(self, title=title, tooltip=tooltip, action=close_panel, icon_name='times')
+        def action():
+            close_panel()
+            if close_callback is not None:
+                close_callback()
+        BarState.__init__(self, title=title, tooltip=tooltip, action=action, icon_name='times')
 
 class UIState:
 
@@ -69,8 +74,9 @@ class UI:
         self.top_bar = TopBar(book_list_container)
         self.books_view = BooksView(interface_data, book_list_container)
         self.items_view = ItemsView(interface_data, book_list_container)
+        self.prefs_panel = PrefsPanel(interface_data, book_list_container)
         self.search_panel = SearchPanel(interface_data, book_list_container)
-        self.panels = [self.books_view, self.items_view, self.search_panel]
+        self.panels = [self.books_view, self.items_view, self.search_panel, self.prefs_panel]
         self.panel_map = {self.ROOT_PANEL: UIState(create_book_view_top_bar_state(self.books_view), main_panel=self.books_view)}
         self.current_panel = self.ROOT_PANEL
         window.addEventListener('resize', debounce(self.on_resize.bind(self), 250))
@@ -84,8 +90,13 @@ class UI:
         self.panel_map['booklist-sort-menu'] = UIState(ClosePanelBar(_('Sort books')), panel_data=def():
             return self.books_view.sort_panel_data(create_item)
         )
+        self.panel_map['booklist-config-tb'] = UIState(
+            ClosePanelBar(_('Configure Tag Browser'), close_callback=self.search_panel.apply_prefs.bind(self.search_panel)),
+            main_panel=self.prefs_panel, panel_data=self.search_panel.get_prefs.bind(self.search_panel))
 
-        self.panel_map['booklist-search'] = UIState(ClosePanelBar(_('Search for books')), main_panel=self.search_panel)
+        bss = ClosePanelBar(_('Search for books'))
+        bss.add_button(icon_name='cogs', tooltip=_('Configure Tag Browser'), action=show_panel_action('booklist-config-tb'))
+        self.panel_map['booklist-search'] = UIState(bss, main_panel=self.search_panel)
 
     def on_resize(self):
         pass